Terrestrial Trunked Radio (TETRA) (formerly known as Trans-European Trunked Radio) is a professional mobile radio and two-way transceiver (colloquially known as a walkie talkie) specification. TETRA was specifically designed for use by government agencies, emergency services, (police forces, fire departments, ambulance) for public safety networks, rail transportation staff for train radios, transport services and the military.

TETRA is an European Telecommunications Standards Institute (ETSI) standard, first version published 1995; it is mentioned by the European Radiocommunications Committee (ERC)

Videos:

Making Waves: Microwave Pollution (preview)

On 15 March 2005, Karen Naismith Robertson of the North Dorset Green Party presented a national 'TETRA and Phone Mast Forum' in Gillingham, Dorset, UK. The event was filmed and made into a DVD-ROM to make the information available to the wider public. The Forum was chaired by Mike Bell of the EM-Radiation Research Trust and the list of speakers included: